1 - Alaska Energy Data Inventory

increase the Polar Moment of Inertia (WR2) from the 1,075,000 lb-ft 2originally recommended. When WR 2 was increased to 1,300,000 lb-ft 2 ,the system showed itself to be stable with the recommended 10 ft diametersurge tank.c. Temporary Speed Droop - After a number of t ri a 1 s, it wasdetermined that by increasing the temporary speed droop (~) from 0.23("first cut" value) to 0.40, "WHAMO" showed the system to be stable (withthe design surge tank diameter of 10.0 ft), even with the initallyrecommended WR 2 of 1,075,000 lb-ft 2 (Plates B3 and B4). Changing thetemporary speed droop to 0.40 results in a change of coefficient ATHREEfrom 2.18 to 3.31. As a result of this investigation, it is apparent thatthe governing controls will be required to produce the temporary speeddroop required for stabil ity. The stabil ity runs for the 6.0 ft diametersurge tank (Plate B6) and the 7.3 ft diameter surge tank (Plate B5)incorporated the temporary speed droop of 0.40. Fi gure 12 ; n Append i x B2shows the input file used for the recommended 10 ft surge tank.d. Electrical Governor - the above analysis was made for amechanical governor, but it now seems likely that an electric governor willbe installed (the current version of the governor specifications give thecontractor the option of using either).The "WHAMO" input file for stabil ity was modified to include anelectric governor. Some additional minor power conduit changes requestedby HE DB were also incorporated and are shown on Figure 22 in Appendix B2.The input file appears as Figure 23 in Appendix B2. In specifying theelectric governor, the following values were recommended by HE DB and wereused in the program:Proportional GainIntegral GainDerivative GainSpeed regulation= 3.460= 1 .090= 0.275= 0.050Pilot Servomotor time constant = 0.050Bl-33